Electrode for electric-arc lights.



n. JONES. `BLHCTBODE POB ELECTRIC ABO LIGHTS.

APPLIOATIOH FILED APE.-19, 1909. V

Patelitd NDV. 1, 1910.

/wM,7/m/a@mwm ad;

ADRIAN DENMAN JONES, 0F HOLLOWAY, ENGLAND.

ELECTODE FOR'I'ELECTIRIC-ARC LIGHTS.

Specification of Letters Patent.

Patented Nov. 1, 1910.

Application filed April 19, 1909. Serial No. 490,945.

the like in a Carbon electrode may become disintegrated when heated by proximit to the arc and tend to crumble away or i the electrodes .are subjected to rough usage may become detached and fall away from the carbon core. It has hereforc, been necessary to employ together with the mixture of chemicals used to fill the grooves or the lile, some substance which gives adhesive properties to the chemical mixture and acts as a cement, and the freedom of choice of a chemical mixture is thus hampered by 'the necessity of considering the bmding qualities as Well as the light iving ropertles of the lconstitutents and t eir e ect on thc steadiness of the arc. 4

The invention consistsv in so shaping a central corel of carbon and a plying the chemical mixture that even ift e chemical mixture does not adhere to the carbon core or support, the chemicals are mechamcally held and do not become com letely detached from the electrode. The car on core or support is therefore formed in'such a manner that the chemicals are mechanically interlocked with the core.

To insure good operation with electrodes constructed according to the invention it is advisable that the chemicals substantially embrace and surround the carbon core. By

' this construction the chemicals serve to protect the carbon from air currents, and thus rolong the life of the electrode, and the car- )on core formsa point of contact for restrikingthe arc when current is first switched on.

'o effect the object of this invention various forms of construction may be used the principle of interlocking the chemical paste and carbon remaining substantially the Same throuffhout.

Witi electrodes of star shaped cross section knobs or projections may be-formed upon the extremities of the rays or flutes, or small fillets or grooves may be formed upon the sides of any suitable fluted or grooved electrodes to give a hole to the paste. Again, the carbon core may have projections or arms radiating. outward and then curvinginward again. In another form the central core may have grooves or fiutings so cut away that the chemical paste dovetails into these grooves or dovctailcd holes may be provided. Generally an electrode of star section with' a large central core of pure carbon und thin radiating armsor ra s which have projections at their ends su cient to mechanically lock the chemical aste, is easy to manufacture and quite satis aetory.

Referring more particularly to the drawilws, the black portion in the various figures indicates carbon, the shaded or dotted portion indicating the chemical mixture sur` rounding the carbons. All the figures are cross sections of the electrodes.

Figure 1 shows a grooved or star shaped carbon, with the ends of the ra s sufficiently thickened to form a I ne'chanicalY lock for the chemicals. Fig. 2 shows the rays or arms bentto lock the chemicals within the arms. Fig. 3 shows projecting fillets upon the rays or arms of the star. Flg. 4 shows roughened edges u on the rays or arms. Fig.`5 shows a raye y carbon wlth locking projections or fillets on the end of the radial arms, but for ease of manufacture I prefer the form shown in Fig. 1.

It is obviousl that the various forms may be modified, retaining the principle of a central carbon core with flutmgs or projections mechanicall 4holding the chemicals which substantial the main body of t 1e carbons.

'Having now described my invention what I claim as new and desire to secure by Letters Patent is 1. An arc lamp electrode, comprising a embrace and surround carbon core, a plurality of projecting members from said core, iemical material disposed around the core between said projecting members, and Saul projecting members being shaped so as to partially inclose tions coperatng therewith and with the 10 said chemical material, to mechanically hold chemical material to mechanically hold the it in lace. latter in place.

2. n arc lamp electrode comprising a In testimony whereof, affix my signacarbon core provided with a plurality of ture in presence of two Witnesses. radial members, and chemical. material dis- ADRIAN DENMAN JONES.

posed around the core between said radial \\='itnesses: ,nuernberg each of said radial members on the ALBERT E. BAnKEn,

B. CLARK.

carbon core provided with lateral projec- 

